Separation of substances by the wet magnetic process.



G. U'LLRIGH. SEPARATION OF SUBSTANCES BY THE WET MAGNETIC PROCESS.

APPLIGATIQN FILED DEG.23, 1909 Patented May 20. 1913.

UNITED OFFICE.

GEORG- ULLBICH, 0F MAGDEBURG, GERMANY, ASSIGNOR TO FRIED. KRUPP AKTIEN- GESELLSCHAFT GRUSONWERK, 0F MAGDEIBURG, GERMANY.

SEPARATION OF SUBSTANCES BY THE WET MAGNETIC PROCESS.

Specification of Letters Patent.

Patented May 20. 1913.

Application filed December 23, 1909. Serial No. 534,718.

- liquid walls or columns.

This invention relates to the separation of substances by the wet magnetic process. If ma nctic material is to lee-separated from slig tly magnetic or nonmagnetic material by extracting it from a liquid by means of a magnet or a magnetizable body moving to ant. fro or fixed above the liquid, the surface tension of the liquid exerts considerable impediment to the extraction which has to be overcome by an intensity of magnetic excitation considerably exceeding that which is necessary for the dry separation over these materials. The advantages of wet separation over dry separation are therefore nullified owing to the increased expense for electric current.

By means of the present invention these difficulties are uvcfironn: by forming liquid wa ls or columns between the surface of the liquid flowing over the pole of a magnet and carrying with it the material to be separated, and the conveyor device employed for carry ing off the magnetic malcrmhwvhich device is arranged above said liquid and at an appropriate distance therefrom. In these liquid walls or columns the magnetic particles are lifted as far as the lower face of the conveycr device with the assistance of buoyancyand without having previously to lea e the liquid, in such a manner that they are carried away from the magnetic field while adhering to the conveyor device. This process not only renders it possible to sepa rate by the Wet process slightly magnetic material, the Wet separation of which has heretofore been impracticable, but also to economize electric current as compared with the dry separating process.

The conveyer device may consist of magnetic or non-magnetic material. In the latter case it may be covered with magnetiz'able bodies. When the conveyor device employed is entirely non-magnetic, it is necessary to provide in addition to the magnets beneath the liquid an upper magnet comprising one or a plurality of downwardly directed edges or points below which the conveyer device moves.

If the conveyer device is entirely magnetic or provided with magnetizable bodies, the

upper magnet described may likewise be provided, or the entire conveyer device or its magnetizable bodies may be energized by the lower magnets, in which case they should be provided with sharp edges or points on their lower face.

In order to form the liquid walls or columns, the conveyer device is conducted over the liquid stream at a distance from its surface suited to the permeability of the magnetic material to be separated. The magnetic lines of force condense at the edges or points of the upper magnets or of the conveyor device, so that in many cases the magnetic particles are directly attracted by the conveyer device. The particles carry liquid with them which adheres to the conveyer device or its magnetized edges or points and thereby forms, between the liquid s1 ream below and the conveyer device above, thin walls or columns which are constantly renewed by the attraction of other magnetic particles and in which walls the latter are attracted onto the conveyer device without having previously been withdrawn from the liquid.

If at the beginning of the operation the attraction of the magnet particles and consequently the formation of the liquid walls, does not take place itself, this action is assisted by employing at the start an electric current of greater intensity for energizing the magnets; or the upper magnet and with it the conveyor device (or the latter alone if it is magnetizable) are brought so close tothe surface of tlre liquid, that the walls are formed, whereupon the normal strength of current or the normal interval can be reestablished, Either of these methods involves initial increase in attraction exerted upon the material, followed by a return of normal attraction.

Owing to the liquid walls or columns, the height of the layer ofliquid is increased at these places. Accordingly the force of buoyancy acts'upon the material to be attracted throughout the entire height so that greater opportunity is afforded for washing off any non-magnetic material adhering to the magnetic particles.

The liquid connection between the conveyer device and the surface of the pulp produced in the manner described above can also be effected by continuously spraying the conveyer device from above. With this object the coir'eyer device is for instance formed of permeable material or provided with fine openings, or the magnetizable edges and points are provided with openings leading downward, from which the liquid issues continuously in the form of bands or threads in such a manner, that an uninterrupted liquid connection is established between these places and the surface of the pulp in which the magnetic particles are raised; One can also convey the pulp to the points or edges by means of stationary water conduits such as ring-shaped tubes provided with tiny holes, etc. As the spraying of the points or edges is opposed to that of the ascending magnetic particles, the liquid will exert a still more vigorous cleansing action upon these particles than in the arrangement previously described. The conveyer device used for carrying 011' the separated magnetic material may in either case consist of plates, rollers or bands and it may serve a number of magnetic fields.

In the accompanying drawing, Figs. 1, 2, 3 and 4: illustrate four examples of the formation of liquid walls or columns, in cases in which a conveying device b, b, b or b for the separated magnetic material consists of magnetizable material, without, however, referring to a given magnetic separator; construction. It is assumed in.the examples that theore separator consists of lower stationary magnet poles 0 upon which a conveyer channel e, for the Wet material to be separated, rests, and over which a magnetizable ring b, b, b or b, the cross section of which is rectangular above and tapered below and which serves for carrying away the separated magnetic material, rotates about ,a vertical axis. This arrangement is not essential, however, and can be replaced by any other suitable arrangement.

Fi s. 1 and 2 illustrate the manner in whic liquid is simultaneously supplied to the edge of a ring I), from above, in order to cause the formation of the liquid walls or facilitate such formation, so that the interval between the channel and the ring can be larger than is otherwise possible.

In Fig. 1, the ring b carries a channel f receiving the upper li uid, holes g leading from this channel to tie lower edge of the ring or the points or other protuberances situated on the lower edge.

In the construction illustrated in Fig. 2, the liquid is conducted to the lower edge of the ring I), from above also, but through lateral tubes b so that it runs down the angularly disposed faces.

Fig. 3 is an elevation of an annular member 6 showing the formation of a liquid wall in accordance with Fig. 2. The separated magnetic material is removed from the magnetic fields by the ring 6 moving in the direction indicated by the arrow and delivered to the vessels i arranged betvveen the magnet poles.

Fig. 4 is an elevation of an annular member [1 provided with means for conducting the liquid from above, corresponding to Fig. 1, and below with points, in which the holes g open. The liquid columns Z, here formed, correspond to the points of the ring; It will of course, be understood that this method of conducting the liquid to the lower edge of the ring can be utilized in connection not only with points but also with other appropriate formations.

-Having thus described m invention, what I claim as new therein an desire to secure by Letters Patent is:

l. A wet magnetic process for separating material consisting in the formation of a vertically and downwardly flowing liquid wall in a magnetic field, delivering material to be separated to said wall in a direction transverse to the flow of liquid; and in magnetically raising the magnetizable particles of said material in said liquid wall andthen conveying them out of said wall to a point of de osit.

2. wet magnetic process for separating material consisting in the formation of a vertically and downwardly flowing liquid wall in a magnetic field, delivering material to be separated to said wall in a direction transverse to the flow of liquid and in magnetically raising the magnetizable particles of sald material in said liquid wall and then magnetically conveying them out ofsaid wall to a point of deposit.

3. A method of separating substances, consisting in creating a downward stream of liquid in a magnetic field, passingthe material to be separated transversely through said stream, magnetically intercepting. the

magnetizable material in said stream and livery to the Wall and against the flow. and removing the same out of the normal path separately discharging the separated parof material through said stream. tieles.

4. A method of separating substances, The foregoing specification signed at 5 consisting in creating in a magnetic field a t Magdeburg, Germany, this seventh. day of '15 laterally unsupported wall of downwardly December, 1909. flowing liquid, delivering material to be; GEORG ULLRICH.

separated into said wall transversely to the In presence of flow, magnetically dnerting the magnetizlVnJiELM Inmscnnnun,

10 able partit-les out of the normal path of de- OSKAR MARKISCH. 

